In installations for coating a web-form material, typically a web of a synthetic film, a first web drum is unwound, the wound-off web is coated, for instance by sputtering, and the coated web is wound up again on a second web drum. When the first web drum has been fed out completely, it must be replaced by a new and full web drum. In addition, the coated web, which is completely wound-up on the second web drum, must also be removed and be replaced by an empty web drum. The term web drum is also referred to herein as web roll.
In known arrangements and methods for coating a web-form material, the steps of winding up and unwinding the web-form material are conducted in winding up and unwinding chambers being separated from the coating sites. For replacing the web drums, a crane may be used to remove the web drums out of the winding up and unwinding chambers and to introduce new web drums into the chambers from above.
Sometimes the uncoated fresh web-form material has not been wound up properly such that the lateral edges of consecutive layers of the film on the web drum are not positioned exactly on top of each other, resulting in a lateral winding deviation. Such a winding deviation, however, may result in an undesirably laterally shifted coating of the web-form material during coating processing. In addition, after coating processing the coated web-form material may be wound up in a laterally shifted way, which may be undesirable for a subsequent application of the coated web-form material.